Filtering system



Sept. 20, 1949. o. M. SIJMMERS 2,482,362

FILTERING SYSTEM Filed April 25. 1946 5 Sheets-Sheet 1 uvEN TOR 86 orroM. SUMMERS Sept. 20, 1949. o. M. SUMMERS FILTERING SYSTEM 5 Sheets-Sheet2 Filed April 25, 1946 Iuvsurcm OTTO M. SUMMERS QT 5W ATTORNEY!) P 1949-o. M. SUMMERS 2,482,302

FILTERING SYSTEM Filed April 25. 1946 5 Shee'ts-Sheet 5 I "reams OTTO M.SUMMER Ar-roRNEyz 5 Sheets-Sheet 4 m MM 7 m w m 5 m w 0 Q Q N 5 a F 0Sept. 20, 1949. o. M. SUMMERS FILTERING SYSTEM Filed April 25, 1946 H hEm nn 9 w rill I/ 7 vnw aa .voulllllb'dlt g 6 ll 00 l ZVIAVIV/l? 4 Sept.20, 1949. o. M. SUMMERS 2,482,302

FILTERING SYSTEM 5 sheets-sneak 5 Filed April 25, 1946 INVENTOR OTTO MSUMMERS Patented Sept. 20, 1949 FILTERING SYSTEM Otto M. Summers,Glasgow, Ky., assignor to The Thompson Grinder Company,

Springfield,

Ohio, a corporation of Ohio Application April 25, 1946, Serial No.664,919

13 Claims. (Cl. 210-190) This invention relates to filtering systems andparticularly to filtering systems for use in connection with machinetools such as lathes, grinders, etc. which have circulating cooling orlubricating fluids.

In machine work it is usually necessary to bathe the cutting member andthe workpiece being cut with a lubricant or a coolant in order to beable to produce high quality products at the rate of speed necessary foreconomical production. The fluid so employed is circulated from a sumpor reservoir by a suitable pumping means and is returned to thereservoir, generally by gravity flow.

Since machining operations remove metal from the workpiece, the coolingor lubricating fluid picks up small particles of material during itspassage through the aforementioned circulatory system. In many cases,especially in the case of grinding machines, a good bit of the particlesthus picked up are very fine and have a tendency to be carried with thefiuid completely through the system and returned to the point of use ofthe fluid. This is undesirable in that a workpiece having a high finishcan only be produced if the cooling and lubricating fluid is free ofparticles of metal and abrasive.

The fluid is also sometimes employed for lubricating the machine waysand, to this end, is preferably free of all particulate foreign materialsuch as dust, metal fragments and abrasive residue.

Accordingly, it is important that the fluid be properly and adequatelyfiltered and this filtering action is preferably a continuous process sothat the fluid is maintained in a clean and useable condition at alltimes.

The principal object of the present invention is to provide a filteringsystem which has a high degree of efficiency in removing particles andwhich is readily serviced and cleaned. The inherent and basic means bywhich this exceptionally high degree of efiiciency is accomplished in alarge volume of coolant liquid with a minimum of flow resistance, andwhich differentiates this system from conventional types, is thearrangement of large area bags of relatively coarse and highlyadsorptive fabric with restrictive overflow means, in such manner as toagglomerate by adsorptive action and permanently trap exceedingly fineparticles which are removed from the system through the routine changeof filter bags.

This agglomeration is a constant process and while maximum effect isachieved in that portion of coolant fiuid that passes through the coarsemeshes of the fabric, it acts with only a slight decrease in eificiencyon the portion that overflows, when the timely replacement of bags isneglected.

This arrangement assures a positive and unfailing fiow of coolant liquidunder any and all conditions, which is an absolute requisite of apractical grinding operation, as a sudden reduction of flow of as littleas 10% would under some conditions result in a total loss of theworkpiece as well as partial loss of wheel form.

Another object is to provide a filtering system for fluids such that theresidue collected by the filter is easily removed therefrom to place thefilter in clean condition.

Another object is to provide a filtering system in which there is anauxiliary reservoir that collects the residue.

Still another object is to provide a filtering system in which the fluidbeing filtered is passed through a filtering medium which agglomeratesthe exceedingly fine particles into particles of greater size which aremore easily separated from the fiuid either by straining or by settling.

These and other objects and advantages become more apparent uponreference to the following specification taken together with theaccompanying drawings in which:

Figure 1 is a perspective view of a grinding ma chine having a filteringsystem according to this invention. associated therewith;

Figure 2 is a plan section taken substantially along the line 22 ofFigure 1;

Figure 3 is a vertical section taken substantially along the line 3-3 ofFigure 1 and showing the primary and secondary filtering units;

Figure 4 is a vertical section taken along the line 4-4 of Figure 3showing the primary filtering unit and the auxiliary settling ordiffusing tank;

Figure 5 is a section on the line 5-5 of Figure 4 and shows the settlingor diffusing tank more in detail;

Figure 6 is a section taken on the line 66 of Figure 1 and shows thepumping units;

Figure 7 is a fragmentary view showing the manner of suspending thefiltering bags in the units;

Figures 8 and 9 are fragmentary views showing tdetails of the controlvalves in the filtering sys- Figure 10 is a perspective View of the topof a tank showing a partition dividing the tank into upper and lowerportions; and

Figure 11 is a vertical section taken intermediate the section shown inFigure 3 and the rear the path of fluid flow through the primary andsecondary filters.

Referring to the drawings, there is shown a grinder in Figure 1 having abed l and a table I2 reciprocable thereon. A grinding wheel at M isdriven to grind work carried on the table i2.

Located adjacent the machine, and preferably to the rear ti'iereer, isthe filtering system of this invention generally indicated by thereference numeral [6. Preferably, the unit forms a portion of the bed ofthe machine in order to elin iinate as much of the external bulk aspossible but for the sake of clarity,'the filtering mechanism has beenillustrated the diawing s as an entirely separate apparatus.

The filtering system supplies cooling or lubri- V eating fluid through aflexible conduit 18 to a nozzle 20 adjacent the wheel M so that thefluid can be sprayed directlyon the wheel and workpiece at their pointof 'contact.The fluid so sprayed on the wheel anclwork drains onto thetable l2 and thence into a passage in the bed which terminates in adischarge conduit 22 that retur'risthe u's'ed fluid to the filteringsystem.

Referring to Figures 2, 3 and 4, the filtering system will be seen tocomprise a pair of sumps, tanks or reservoirs 24 and 26within which aresuspended the filterin bags 28 and so respectively. The bags arepreferably provided with a ring as at 32 around their upper, open endswhich rests on a ledge '34 fixedly attached to the tank. Thestructure, 1. e., partition 36, extends to the tank walls and divides*it into upper and lower 'aaits so that fluid passed into either of thetanks at the top will be directed into the filter bag therein.Preferably, and for a reason to become more apparent hereinafter, the-ledge 34 is suspendeairem the partitions 3'6 by a-s'lee've 3 8 hav -ing a plurality of overflow apertures 40 therein. The filtering bags are'a fabric of any suitable material and permit relatively free flow offluid theretl'irough while retaining'substantially all oftliepartlcula'te foreign material within-the bag.

The fluid to be filtered enters the tank 124 from tlie'c'on'duit "22above thebag 28 and pours into the filter bag 28. The fiuid pa-ssesthrough this bag and collects in the space between the bagand the tank.The fluid level in the tank around the bag 28 gradually rises -unti1 itoverflows into the upper part of the tank 26 by meansof the passage 42(Figures 2 and 4) extending between the tanks. This overflow, it will benoted, s'pills into the open upper end of bag '30. It will be noted that-the lowermost portion of the passage 7" '42 is somewhat below the topof the primary filter bag 28 so that normally there is a substantiallygreater head on the fluid int-he bag 28 than in the lower part of thetank 24 before thebag will be filled to overflowing.

Th fluid that "pours into the secondary filtering bag passes through thesaid baganol collects in the lower part of tank 26 in the space aroundthe bag 30. This fluid rises in the tank until it reaches a level thatwill permit itto pass through the aperture 44 and into the chamber 46.The chamber 46 is between the tanks 24am *26 andis best seen in Figures'3and6; Within the chamber 46'is'a pump' 48 which is driven by a motor50 which is preferably vertically mounted and has itsdrive "shaftextending downwardly into engagement with the drive shaft of said pump.The pump draws-'fluid'from'thechamber 46 and discharges the saidfluidintoa conduit 52 which extends upwardly and is connected with theaforementioned flexible conduit l8 which leads to the spray nozzle 28adjacentthe grinding wheel. The circulatory system described aboveconsists of the main flow channel for the fluid to be filtered. It willbe noted that this fluid flows by gravity through a primary filteringelement, then passesto a secondary filtering element and newstherethio'ugh by gravity, and finally is pi'ekd up by the circulatingpump.

The area of each of the primary and secondary filtering elementsis largeand the area of each of the primary and secondary reservoirs is alsorelatively large so that the flow of fluidthrough the filteringsystem.is relatively slow. This gives the particulate material carried by thefluid time 'to -settle 'out' so that any foreign matter passedthroughthe bags is largely collected as a sludge in'the primary andsecondary reservoirs.

Referring to Figure 3, it will be noted that the primary reservoir 24has a sloping bottom plate 54 while the "secondary reservoir also .has abottom plate 56 which is inclined downwardly toward the center'of thefiltering apparatus. Between the filtering reservoirs and beneath thechamber 46 is another chamber 58 which is communicable with thereservoirs '24 and "26 7 through the :apertures "60 and "62 respectivelywhich open'in-to the-said tanks at their lowest points. Each of theapertures Gil-and 62 is adapt ed for being closed by a resilient valvemember 64 movable into engagement therewith by a lever extendingupwardly through the chambers 58 and 46 and into an-open well or recess66 between the tanks 24 and 26., This well may also'house =the=m0tor50ifdesired. I V

The valve actuating levers, indicated at 68 engage the rods 'H) passingthrough the said valve members and are 's'ealed in their passage throughthe bottom Wall 12ofthe chamber 46 by the' rube her-like blocks 14.These blocks are best-seen in Figure '9 and 'it will be apparent thatthey can eifect an adequate seal without hindering the angular movement'of the rods 68. In Figure '8, it will -be -noted that the rods '18 arepassed through blocks '16 secured'to the' botto'in walls of thefiltering reservoirs so that theresilient valve members 64 are guided"to and from their seated position.

-In -Figure'2, --it will be-seen that each of the rods 68'extendsthrough the upper wall 18 ofthe chamber 46 through a slot 88 which hasone end offset substantially 'at right angles so that the rods may eachbe-locked in the position in which diffusing the tank 90 has suspendedtherein a relatively coarse fabric sleeve 92. The opening of the sleeve92 is covered by a perforated plate 94. This assembly is suspended froma plate 96 which is centrally apertured to receive the end of theflexible conduit 88. Fluid delivered through the conduit 28 isdischarged onto the plate or tray 94 and passes therethrough into thesleeve 92 and is filtered partly through the said bag into the tank 90.More specifically, the action of the sleeve 92 is to diffuse and slowdown the travel of the fluid so that the foreign particles entrainedtherein have the maximum opportunity to settle out as a concentratedsludge indicated by the stippling at 98 in Figure 5. The tank 90 isprovided with a pair of conduits I00 which pass through the tank andwhich have the openings I02 therein through which the filtered fluid inthe tank overflows. The conduits I00 also serve the purpose ofsupporting the plate 96 and terminate at their open ends in an elbow orbent portion I04 which opens into the primary filtering bag 28. Theprimary filtering tank 24 is preferably closed with a removable lid I06which is apertured as at I08 to receive the elbows I04. The aperturesI08 and the elbows I04 provides means of suspending the tank 90 on thefilter. The tank may thus be removed quite easily for removing thesludge therefrom.

When it is desired to clean the sludge tank 90, both of the apertures 60and 62 are closed by their valve members so that the chamber 58 becomestightly closed. Thereafter, the pump 8'2 will withdraw fluid from thechamber 58 and create a suction therein which also stands in the conduitIIO. Conduit IIO extends upwardly substantially parallel with theconduit 84 and has its lower end opening into the chamber 58. The upperend of the conduit I I0 has a shut-off valve II2 from which extends afitting or pipe nipple I I4. When the tank 90 is to be cleaned, theplate 96 and the bag 92 carried thereby are lifted from the said tankand are placed in the upper part of the primary filtering tank 24. Aflexible conduit or hose is then attached to the nipple H4 at one endand the other end placed in the tank 90.

Then, when the valve I I2 is opened the suction in the chamber 58 iseffective to draw the fluid from the tank 90 and to discharge it throughthe conduits 84 and 08 into the bag 92 whence the fluid passes into theupper part of tank 24 and to the primary filtering bag 28. When th fluidhas been drawn off from the tank 90, the tank may be lifted from themachine and the sludge removed therefrom. The cleaning of the sludgetank is now completed and it may be reassembled and placed intooperation.

It will be noted that any of the bags of the several filtering units canreadily be removed from its reservoir for cleaning or replacement.

Thus, if desired, the bags may be cleaned or replaced daily and thesludge tank cleaned out as often as is necessary. This insures acontinuous supply of clean cooling or lubricating fluid at all times.

Should the amount of fluid being circulated through the system exceedthe capacity of any of the filtering bags, the excess fluid willoverflow through the apertures 40 in the bag suspending sleeves so thatthere is no discontinuance of the operation of the circulatory system.

It will be understood that this invention is susceptible to modificationin order to adapt it to different usages and conditions and,accordingly,

it is desired to comprehend such modifications within this invention asmay fall within the scope of the appended claims.

I claim:

1. In a filter; a pair of units each comprising a tank having atransverse apertured partition therein, the partition of the first tankhaving a greater elevation than the partition of the second tank; afilter bag in each tank suspended at its open end from the partition atthe periphery of the aperture therein; a conduit connecting one of thetanks exteriorly of its bag and beneath the partition therein with theinterior of the bag of the other of the tanks above the partitiontherein; a pump having its inlet connected with said other tankexteriorly of the bag and beneath the partition therein and adapted fordischarging to a work station; a fluid inlet discharging from a workstation into said first tank above the partition therein; a sump andmeans for selectively connecting and disconnecting said sump with thelowermost part of at least one of said tanks; a third tank having afiltering element therein; and conduit means connected to convey fluidfrom the sump through said third filtering element and into said firsttank above the partition therein. 7

2. In a filter; primary and secondary units each comprising a tankhaving an apertured transverse partition therein, the partition of thefirst tank having a greater elevation than the partition of the secondtank; a filter bag in each tank suspended at its open end from thepartition at the periphery of the aperture therein, said partitions andfilter bags cooperating to divide said tanks into upper inlet and loweroutlet compartments; means connecting the upper part of the primaryoutlet compartment with the secondary inlet compartment; a pumpconnected to the upper part of the secondary outlet compartment to drawfluid therefrom and to discharge it to a work station; a fluid inletconnection to the inlet compartment of the primary unit; a thirdfiltering unit having an inlet and outlet; conduit means connecting theinlet of said unit with the bottom of the tank of said primary elementand the outlet of said third unit with the inlet compartment of saidprimary element, said third filtering unit comprising a tank ofsubstantially greater area than said conduit means and a verticalforaminous barrier arranged between the inlet and outlet whereby fluidflowing from said conduit into said tank will slow down and diffusethrough said barrier while th particulate matter entrained therein willhave a tendency to be precipitated to the bottom of the tank, andpumping means for forcing fluid through said conduit means to the inletof said third unit.

3. In a filtering system, a pair of tanks, transverse partitions in theupper parts of said tanks at different levels thereof, a channelextending substantially horizontally between said tanks from beneath thehigher of said partitions to above the lower thereof, said partitionshaving a large central aperture and an open filtering bag in each tanksuspended at its open end from each partition at the periphery of theaperture therein, said partitions and bags thereby dividing each tankinto upper and lower compartments, a sump connected with the upper partof the lower compartment of the tank having the lower partition, a pumphaving its inlet connected with said sump and operable to draw fluidtherefrom and for conveying it to a work station, an inlet connection inthe upper compartment of the tank having the 9 i tray over the upper endof said element and into which said pump discharges, and overflow meansconnecting the upper part of said tank around said sleeve with the uppercompartment of one of said reservoirs.

9. In combination with a filter tank having an apertured transversepartition and a filter bag suspended at its open end from the partitionat the periphery thereof separating the tank into an inlet section and asettling chamber, a tank open at the top, a relatively coarse perforatedsleeve vertically arranged in said tank, a perforated plate at the upperend of said sleeve and through which fluid passes to the interior ofsaid sleeve, means supporting said sleeve and plate, an overflow in theupper part of said tank outside said sleeve for discharging fluid fromthe space between said sleeve and said tank, and pumping and conduitmeans to convey fluid and sludge from said settling chamber to saidplate, whereby the fluid passes through the plate into the sleeve,diffuses outwardly through the walls of said sleeve and the particulatematerial entrained therein has a tendency to be precipitated to thebottom of the tank.

10. In combination with a filter tank having an apertured transversepartition and a filter bag suspended at its open end from the partitionat the periphery thereof separating the tank into an inlet section and asettling chamber; means for treating fluid and sludge from said chamberand to efiect a substantial separation of fluid from the said sludge andto return fluid to the filter, said means comprising: a tank, arelatively coarse perforated sleeve vertically suspended in said tank,and open both top and bottom, a perforated plate across the upper end ofthe sleeve through which fluid and sludge passes to said sleeve,overflow conduits extending into said tank outside said sleeve adjacentthe upper end of the sleeve to convey fluid from the space between saidsleeve and said tank to the filter, and means supporting said plate andsleeve on said conduits.

11. In a filter; a primary settling reservoir having a transverseapertured partition and a primary filter bag detachably suspended fromthe periphery of the aperture in the partition; a secondary settlingreservoir also having an apertured partition set at a lower elevationthan the primary reservoir partition, and a secondary filtering bagdetachably suspended from the periphery of the aperture of the saidpartition; channel means connected from beneath the partition in theprimary reservoir to above the partition in the secondary reservoir; aclosed sump connected with said secondary reservoir beneath thepartition therein to receive filtered fluid therefrom; pumping means forforcing fluid from said sump to a work station from which the fluidreturns to the space above the partition in said primary reservoir; achamber between said reservoirs at the bottom thereof; valve meansoperable selectively to connect and to disconnect said chamber with thelowermost partitions of said reservoirs or for closing said chamber; apump having its inlet opening into said chamber and an outlet; a tank; arelatively coarse perforated sleeve vertically suspended in said tankand open both top and bottom; a flexible conduit connecting said pumpoutlet with the upper open end of said sleeve; overflow channel meansconnecting the upper part of said tank outside said sleeve with the saidprimary reservoir above the partition therein; and an auxiliary conduitopening into said chamber and having a flexible portion whereby, uponactuating said valves to close said chamber, placing the end of saidconduit in said tank and actuating said pump, the fluid may be drawnfrom said tank preparatory to cleaning the sludge therefrom.

12. In a filter; a plurality of serially connected filtering units eachhaving a, settling reservoir; a, closed sump connected to receive sludgeand fluid from said reservoirs; a diffusing chamber adapted with aninlet to receive sludge and fluid from said sump and having an outlet,said chamber including a foraminous barrier between said inlet andoutlet to direct the sludge toward the bottom of the chamber whilesubstantially clean fluid will pass to the said outlet; a pump havingits inlet in communication with said sump; a plurality of valve meansselectively operable to connect and to disconnect said sump with saidreservoirs or with said chamber; and passage means for selectivelyconnecting the outlet of said pump with the inlet of said chamber orwith the inlet of said filter.

13. In a filter; a pair of units each comprising a tank having atransverse apertured partition therein, the partition of the first tankhaving a greater elevation than the partition of the second tank; afilter bag in each tank suspended at its open end from the partition atthe periphery of the aperture therein; a conduit connecting one of thetanks exteriorly of its bag and beneath the partition therein with theinterior of the bag of the other of the tanks above the partitiontherein; a pump having its inlet connected with said other tankexteriorly of the bag and beneath the partition therein and adapted fordischarging to a work station; a fluid inlet discharging from a Workstation into said first tank above the partition therein; a sump andvalve means for selectively connecting and disconnecting said sump withthe lowermost part of at least one of said tanks; a third tank having afiltering element therein, and a second pump having conduit meansconnected to convey fluid from the sump through said third filteringelement and into said first tank above the partition therein.

OTTO M. SUMMERS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 681,477 Franke Aug. 2'7, 1901985,961 Ten Winkel Mar. '7, 1911 1,081,082 Alden Dec. 9, 1913 1,271,925Moore July 9, 1918 1,462,048 Richards July 1'7, 1923 1,936,315 TillmanNov. 21, 1933 1,959,623 Gordon May 22, 1934 2,044,096 Moran July 16,1936 2,364,418 Barker Dec. 5, 1944 2,396,927 Nelson et al. Mar. 19, 1946

